Interactions between the large-scale radio structures and the gas in a sample of optically selected type 2 quasars

TL;DR

This study investigates how radio structures in optically selected type-2 quasars interact with surrounding gas, revealing that even radio-quiet quasars can have significant radio-gas interactions affecting galaxy evolution.

Contribution

It provides evidence of radio-gas interactions in a sample of non radio-loud quasars, highlighting their potential role in feedback processes across various spatial scales.

Findings

Radio structures are present in most quasars studied.

Evidence of interactions between radio structures and gas in 10 out of 13 quasars.

Large-scale radio sources can exist in radio-quiet quasars, influencing galaxy and circumgalactic medium.

Abstract

The role of radio mode feedback in non radio-loud quasars needs to be explored in depth to determine its true importance. Its effects can be identified based on the evidence of interactions between the radio structures and the ambient ionised gas. We investigate this in a sample of 13 optically selected type-2 quasars (QSO2) at z<0.2 with FIRST radio detections. None are radio loud. All show complex optical morphologies, with signs of distortion across tens of kpc due to mergers/interactions. The radio luminosity has an AGN component in 11/13 QSO2. It is spatially extended in 9 of them (jets/lobes/bubbles/other). The maximum sizes are in the range few kpc to ~500 kpc. Evidence for radio-gas interactions exist in 10/13 QSO2; that is, all but one with confirmed AGN radio components. The interactions are identified across different spatial scales, from the nuclear narrow line region up to tens of kpc from the AGN. Large scale low/modest power radio sources can exist in radio-quiet QSO2, which can provide a source of feedback on scales of the spheroidal component of galaxies and well into the circumgalactic medium in systems where radiative mode feedback is expected to dominate.